The present invention relates to head-mounted video displays and more particularly to head-mounted video display capable of being mounted on the surgeon's head for use as a viewing system for endoscopic surgical procedures.
A head-mounted video display is well known in the art, which is capable of being mounted on the head of an viewer (who wears the display) with an optical system, a video display system, etc., in proper position before the eyes of the viewer, to provide images to the eyes of the viewer. Such a display system has a variety of potential applications.
For example, Japanese Laid-Open Patent Application No. 3-101709 (Literature 1) and Japanese Laid-Open Patent Application No. 3-189677 (Literature 2) disclose helmet systems and helmet-mounted video displays for aircraft crews. The disclosed systems permit viewing electronic subject video and the neighborhood field at the same time. The electronic subject video and neighborhood field are superimposed on each other using a superimposing (combining) unit.
The head-mounted video display (called "HMD") has a display body of goggle type or binocular type, which is capable of being mounted on the head to receive video and audio data transmitted via a cable. This system is attracting attention particularly of the younger generation as a system for enjoying stereo pictures and stereo sounds either indoors or outdoors. Recently, the system is finding applications for surgical purposes: it is worn by a doctor in a surgical site for obtaining video data concerning the surgery and surgical locality of the patient which can not be obtained by observation with the naked eyes. The system can also be switched for observation with the naked eyes, i.e., see-through observation. The present invention especially concerns head-mounted video displays used in the medical field.
For surgery in the surgical room, the doctor should not only sterilize his or her hands but also should not touch what is not sterilized. The doctor, therefore, can not touch the display with his or her hands and has to let an assistant mount the display. However, it has been difficult to let the assistant mount the display to be worn quickly and properly.
The present invention seeks to overcome the above drawbacks, and it has an object of providing a head-mounted video display which permits the user to wear it with his or her own sterilized hands.
As an example, it is conceivable to utilize the head-mounted video display as a surgical electronic subject video monitor using an endoscope having a television camera provided at an end. In this case, with a prior art system where the near-by picture video is superimposed on the electronic subject video, viewing of the details of the surgical site may be difficult because of the interference with neighborhood field. FIG. 33 is a view illustrating this viewpoint, specifically a view showing a case in which the electronic subject video and neighborhood field are superimposed on each other on the head-mounted video display used as a surgical monitor with the purpose of observation by the surgeon. In this case, the surgeon's hands are displayed along with the endoscope and a guide sheath (pierced into the patient's body) thereof and also with a surgical tool and a guide sheath thereof.
This arrangement permits prevention of blood or the like splattering from the surgical site onto the surgeon, thus preventing disease. With the prior art system, however, the electronic subject video picture can not be observed while wearing goggles. That is, it is difficult to protect the eyes and the neighborhood thereof, which is insufficient to provide protection against splattered matter or like external foreign matter.
In view of the above considerations, the present invention seeks to provide a head-mounted video display which permits viewing electronic subject video and the neighborhood field without superimposition thereof and also can appropriately prevent foreign matter from coming through the clearance space between the body of the display and the face of the user wearing it.
The present invention further seeks to provide a head-mounted video display, which, while permitting viewing an electronic subject video picture and a neighborhood field picture without superimposing these pictures, can appropriately guard the face of the wearer, i.e., the surgeon, without wearing any goggles by preventing blood or like matter splattered from the surgical site from being attached to the wearer, so that it is suitable for being worn by the surgeon for surgery or the like.
The present invention still further seeks to provide improvements of such head-mounted video displays.
The doctor wearing the head-mounted video display for medical purpose may view his or her neighborhood from the periphery of the display. That is, the doctor may view the motion of near-by persons or data displayed on various units during the surgical procedures.
In a lenghty, multi-hour surgical procedure, the surgeon views a magnifier as a video display element by holding the line of sight in a horizontal direction.
In the head-mounted video display noted above, the electronic subject video display member is mounted on separate opposite side optical system holders. These optical system holders are coupled together by a coupling member, and mounted on a support member.
In the prior art example of the head-mounted video display as described, however, the support member is disposed such that it greatly blocks the doctor's line of sight (as shown in, for instance, Japanese Laid-Open Patent Publication No. 6-133253). Therefore, the field of view of the doctor, intending to view the neighborhood through the periphery of the head-mounted video display that is worn, is blocked by the support member of the display, and the doctor can not visually recognize motion of a person or data displayed on various units in the neighborhood.
Another drawback in the above prior art example is that the video picture display member is viewed for a long time while holding the pupils in a horizontal direction, eventually resulting in fatigue.
A further drawback in the prior art example is that since the electronic subject video picture display member is mounted on separate opposite side holding members (as shown in, for instance, Japanese Laid-Open Patent Publication No. 3-214872), the holding members may frequently fail to be mounted properly, thus resulting in deviation of the displayed video picture. A still further drawback is the inconvenience due to an increased number of components of the display.
The present invention seeks to overcome the above drawbacks, and it has an object of providing a head-mounted video display which permits observation of the neighborhood of the viewer wearing it through its periphery, also a head-mounted video display which permits less accumulation of fatigue by viewing the video picture display member for a long time, and further a head-mounted video display which is free from deviation of the video picture due to improper mounting of the opposite side holding members, while permitting reduction of the number of components.